1. Field of the Invention
The present invention relates to beach umbrellas and more particularly to an improved beach umbrella having a telescopic shank.
2. Description of Related Art
A conventional beach umbrella is shown in FIG. 16. The umbrella has a large canopy for protection against the sun's rays. As shown, the umbrella comprises a large, metal rod as a shank having a tapered bottom end for ease of inserting into sand. For increasing portability, the shank is made into two separate, connectable pieces (e.g., upper shank R1 having a smaller diameter and lower shank R2 having a larger diameter). In use, simply insert a lower end of the upper shank R1 into a top end of the lower shank R2 prior to turning a lock lever B to fasten them together.
However, the prior art suffered from several disadvantages. For example, the two-piece design tends to cause one or two of them get lost. In detail, a user may forget the exact location of the previously detached upper and lower shanks after a period of time of unused. Thus, a reassembly of the beach umbrella is made impossible when a need for use arises. Also, an adjustment of the shank is impossible due to a fixed length thereof. Thus, it cannot satisfy various length needs of shank desired by users. Moreover, the large shank is not adapted to be used in a small, telescopic umbrella.
As to well known small umbrellas, its shank is made telescopic and has a diameter about 8 to 12 mm and a tube thickness about 0.5 to 0.8 mm. Hence, the shank of the small umbrella is substantially easy to manufacture in a rolling process. To the contrary, the shank of the beach umbrella has a diameter more than 20 mm, a tube thickness more than 1 mm, and a length more than 1.5 m. To the worse, there is little research and development about the improvement of the manufacturing process and associated manufacturing equipment of such beach umbrella due to a very small market. In addition, for protecting a person under the beach umbrella from lightning, the shank of the beach umbrella is typically made of insulated glass fiber as a rod. Hence, the beach umbrella is not adapted to be used in a small, telescopic umbrella. That is why the shank of the typical beach umbrella is made of two pieces. Hence, a need for improvement exists.